Herpes viral infections, including herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) infections, are common infections worldwide. HSV-2 is the cause of most genital herpes and is generally sexually transmitted. In contrast, HSV-1 is usually transmitted via nonsexual contacts. Preexisting HSV-1 antibodies can alleviate clinical manifestations of subsequently acquired HSV-2. Furthermore, HSV-1 has become an important cause of genital herpes in some developed countries. Varicella Zoster virus characteristically produces vesicular pruritic disseminated lesions at varying degrees of maturity. It occurs most frequently in children, with prodromal malaise, pharyngitis and rhinitis, usually with fever and pruritus (chickenpox). Varicella Zoster virus may cause more severe illness in adults, where the lesions are localized and painful, and often involve the trunk (shingles). Additional manifestations of HSV viral infection may include encephalitis and keratitis. Cytomegalovirus is an additional herpesvirus which can cause considerable morbidity in infants and individuals with compromised immune systems.
Although proposals have been made for a cure for the above diseases, an unmet need continues to exist for methods of preventing or treating a viral infection of a host.